simplify function step processing (user reported warnings in data frame conversion)
inject breakpoints on package attach rather than package load
permit breakpoints to be set in loaded (but unattached) package namespaces
Merge pull request #43 from rstudio/bugs/debugging

Fix problems related to breakpoints in packages
set breakpoints on multiple function copies if they exist
Merge pull request #44 from rstudio/bugs/debugging

Fix problems in advanced package breakpoint use
move source urls to notice file
add top-level cmake script for docs
Merge remote-tracking branch 'origin/master' into feature/error-management
simple display of traceback for errors via client event